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1.
Phys Rev Lett ; 127(21): 211603, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34860077

RESUMO

We propose a procedure to determine the moduli-space integrands of loop-level superstring amplitudes for massless external states in terms of the field theory limit. We focus on the type II superstring. The procedure is to (i) take a supergravity loop integrand written in a BCJ double-copy representation, (ii) use the loop-level scattering equations to translate that integrand into the ambitwistor string moduli-space integrand, localised on the nodal Riemann sphere, and (iii) uplift that formula to one on the higher-genus surface valid for the superstring, guided by modular invariance. We show how this works for the four-point amplitude at two loops, where we reproduce the known answer, and at three loops, where we present a conjecture that is consistent with a previous proposal for the chiral measure. Useful supergravity results are currently known up to five loops.

2.
Phys Rev Lett ; 126(10): 101103, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33784125

RESUMO

We establish the status of the Weyl double copy relation for radiative solutions of the vacuum Einstein equations. We show that all type N vacuum solutions, which describe the radiation region of isolated gravitational systems with appropriate falloff for the matter fields, admit a degenerate Maxwell field that squares to give the Weyl tensor. The converse statement also holds, i.e., if there exists a degenerate Maxwell field on a curved background, then the background is type N. This relation defines a scalar that satisfies the wave equation on the background. We show that for nontwisting radiative solutions, the Maxwell field and the scalar also satisfy the Maxwell equation and the wave equation on Minkowski spacetime. Hence, nontwisting solutions have a straightforward double copy interpretation.

3.
Biometals ; 31(6): 927-940, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30117045

RESUMO

Brain-derived neurotrophic factor (BDNF) plays a key role in neural development and physiology, as well as in pathological states. Post-mortem studies demonstrate that BDNF is reduced in the brains of patients affected by neurodegenerative diseases. Iron accumulation has also been associated to the pathogenesis of neurodegenerative diseases. In rats, iron overload induces persistent memory deficits, increases oxidative stress and apoptotic markers, and decreases the expression of the synaptic marker, synaptophysin. Deferiprone (DFP) is an oral iron chelator used for the treatment of systemic iron overload disorders, and has recently been tested for Parkinson's disease. Here, we investigated the effects of iron overload on BDNF levels and on mRNA expression of genes encoding TrkB, p75NTR, catalase (CAT) and NQO1. We also aimed at investigating the effects of DFP on iron-induced impairments. Rats received iron or vehicle at postnatal days 12-14 and when adults, received chronic DFP or water (vehicle). Recognition memory was tested 19 days after the beginning of chelation therapy. BDNF measurements and expression analyses in the hippocampus were performed 24 h after the last day of DFP treatment. DFP restored memory and increased hippocampal BDNF levels, ameliorating iron-induced effects. Iron overload in the neonatal period reduced, while treatment with DFP was able to rescue, the expression of antioxidant enzymes CAT and NQO1.


Assuntos
Antioxidantes/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Deferiprona/farmacologia , Modelos Animais de Doenças , Quelantes de Ferro/farmacologia , Transtornos da Memória/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/química , Fator Neurotrófico Derivado do Encéfalo/análise , Deferiprona/química , Feminino , Hipocampo/efeitos dos fármacos , Quelantes de Ferro/química , Ratos , Ratos Wistar
4.
Phys Rev Lett ; 115(12): 121603, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26430983

RESUMO

The scattering equations on the Riemann sphere give rise to remarkable formulas for tree-level gauge theory and gravity amplitudes. Adamo, Casali, and Skinner conjectured a one-loop formula for supergravity amplitudes based on scattering equations on a torus. We use a residue theorem to transform this into a formula on the Riemann sphere. What emerges is a framework for loop integrands on the Riemann sphere that promises to have a wide application, based on off-shell scattering equations that depend on the loop momentum. We present new formulas, checked explicitly at low points, for supergravity and super-Yang-Mills amplitudes and for n-gon integrands at one loop. Finally, we show that the off-shell scattering equations naturally extend to arbitrary loop order, and we give a proposal for the all-loop integrands for supergravity and planar super-Yang-Mills theory.

5.
Anaerobe ; 30: 116-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25246166

RESUMO

Antibiotic resistance in bacteria is an increasing problem that is not only constrained to the clinical setting but also to other environments that can lodge antibiotic resistant bacteria and therefore they may serve as reservoirs of genetic determinants of antibiotic resistance. One hundred and thirty-six faecal samples from European wild rabbits (Oryctolagus cuniculus algirus) were collected on São Jorge Island in Azores Archipelago, and analysed for Escherichia coli isolates. Seventy-seven isolates (56.6%) were recovered and studied for antimicrobial resistance, one isolate per positive sample. Thirteen (16.9%), 19 (24.7%), 25 (32.4%) and 20 (26%) isolates were ascribed to A, B1, B2 and D phylogenetic groups, respectively, by specific primer polymerase chain reaction. Different E. coli isolates were found to be resistant to ampicillin (16.9%), tetracycline (1.3%), streptomycin (42.9%), sulfamethoxazole-trimethoprim (1.3%), amikacin (1.3%), tobramycin (2.6%) and nalidixic acid (1.3%). Additionally, the blaTEM, tetA, strA/strB, aadA, sul1, intI, intI2 and qacEΔ+sul1 genes were found in most resistant isolates. This study showed that E. coli from the intestinal tract of wild rabbits from Azores Archipelago are resistant to widely prescribed antibiotics in medicine and they constitute a reservoir of antimicrobial resistant genes, which may play a significant role in the spread of antimicrobial resistance. Therefore, antibiotic resistant E. coli from Azorean wild rabbits may represent an ecological and public health problem.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Animais , Animais Selvagens , Açores , Escherichia coli/classificação , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Genótipo , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Coelhos
6.
J Infect Public Health ; 17(5): 810-818, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522155

RESUMO

BACKGROUND: In Europe, up to 70% of visceral leishmaniasis (VL) cases occurring in adults living with HIV. People living with HIV with VL co-infection often display persistent parasitemia, requiring chronic intermittent anti-Leishmania therapies. Consequently, frequent VL relapses and higher mortality rates are common in these individuals. As such, it is of paramount importance to understand the reasons for parasite persistence to improve infection management. METHODS: To outline possible causes for treatment failure in the context of HIV-VL, we followed a person living with HIV-VL co-infection for nine years in a 12-month period. We characterized: HIV-related clinicopathological alterations (CD4+ T counts and viremia) and Leishmania-specific seroreactivity, parasitemia, quantification of pro-inflammatory cytokines upon stimulation and studied a Leishmania clinical isolate recovered during this period. RESULTS: The subject presented controlled viremia and low CD4+ counts. The subject remained PCR positive for Leishmania and also seropositive. The cellular response to parasite antigens was erratic. The isolate was identified as the first Leishmania infantum case with evidence of decreased miltefosine susceptibility in Portugal. CONCLUSION: Treatment failure is a multifactorial process driven by host and parasite determinants. Still, the real-time determination of drug susceptibility profiles in clinical isolates is an unexplored resource in the monitoring of VL.


Assuntos
Coinfecção , Infecções por HIV , Leishmania infantum , Leishmaniose Visceral , Fosforilcolina/análogos & derivados , Adulto , Humanos , Portugal , Coinfecção/tratamento farmacológico , Parasitemia , Viremia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Leishmaniose Visceral/complicações , Leishmaniose Visceral/tratamento farmacológico
7.
Anaerobe ; 23: 82-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23845583

RESUMO

The aims of the study were to analyse the prevalence of antimicrobial resistance and the mechanisms implicated, as well as the virulence factors, in faecal Escherichia coli and Enterococcus spp. from red foxes. From 52 faecal samples, 22 E. coli (42.3%) and 50 enterococci (96.2%) isolates were recovered (one/sample). A high percentage of E. coli isolates exhibited resistance to streptomycin, tetracycline, trimethoprim-sulfamethoxazole or ampicillin (54-27%), and they harboured the aadA, tet(A) and/or tet(B), sul1 and blaTEM resistance genes, respectively. The E. coli isolates were ascribed to the 4 major phylogroups, D (41% of isolates), A (31.8%), B1 (18.2%) and B2 (9.1%), and carried the fimA (63.3%) or aer (13.6%) virulence genes. Among enterococcal isolates, Enterococcus faecium was the most prevalent species (50%). A high percentage of enterococcal isolates showed tetracycline resistance (88%) harbouring different combinations of tet(M) and tet(L) genes. The erm(B) or the aph(3')-IIIa gene were identified in most of our erythromycin- or kanamycin-resistant enterococci, respectively. This report suggests the role of red foxes from rural areas in the cycle of transmission and spread of antimicrobial-resistant E. coli and enterococci into the environment, representing a reservoir of these antimicrobial-resistant microorganisms.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Raposas/microbiologia , Genes Bacterianos , Fatores de Virulência/genética , Animais , Enterococcus/genética , Enterococcus/isolamento & purificação , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Genótipo , Tipagem Molecular
8.
Environ Monit Assess ; 185(1): 59-72, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22322406

RESUMO

The main objective of this work was to quantify and characterize the major indoor air contaminants present in different stages of a municipal WWTP, including microorganisms (bacteria and fungi), carbon dioxide, carbon monoxide, hydrogen sulfide ammonia, formaldehyde, and volatile organic compounds (VOCs). In general, the total bacteria concentration was found to vary from 60 to >52,560 colony-forming units (CFU)/m(3), and the total fungi concentration ranged from 369 to 14,068 CFU/m(3). Generally, Gram-positive bacteria were observed in higher number than Gram-negative bacteria. CO(2) concentration ranged from 251 to 9,710 ppm, and CO concentration was either not detected or presented a level of 1 ppm. H(2)S concentration ranged from 0.1 to 6.0 ppm. NH(3) concentration was <2 ppm in most samples. Formaldehyde was <0.01 ppm at all sampling sites. The total VOC concentration ranged from 36 to 1,724 µg/m(3). Among the VOCs, toluene presented the highest concentration. Results point to indoor/outdoor ratios higher than one. In general, the highest levels of airborne contaminants were detected at the primary treatment (SEDIPAC 3D), secondary sedimentation, and sludge dehydration. At most sampling sites, the concentrations of airborne contaminants were below the occupational exposure limits (OELs) for all the campaigns. However, a few contaminants were above OELs in some sampling sites.


Assuntos
Microbiologia do Ar , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Amônia/análise , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Formaldeído/análise , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Humanos , Sulfeto de Hidrogênio/análise , Exposição Ocupacional/estatística & dados numéricos , Compostos Orgânicos Voláteis/análise
9.
Sci Med Footb ; 7(2): 157-164, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35352621

RESUMO

BACKGROUND: The aim of the present study was to examine the spatial relations between teams (macro-level) and groups of players (meso-level) that afford successful penetrative passes (off-ball advantage) in elite football. METHODS: Three balanced home matches from a Premier League team with 91 ball possessions in which a pass was performed into the opposition defensive area and overpassed the first defensive line, promoting a perturbation of the defensive team equilibrium, were selected for analysis. The spatial relations between teams were measured through spatial variables that captured the areas occupied by the teams, while the spatial relations between players were measured through variables that captured the distances and angles between attacking and defending players near the ball. RESULTS: Results revealed, at the macro-level, higher values of width ratio between teams and the width of the attacking team for unsuccessful penetrative passes (UPP), when compared to successful penetrative passes (SPP). At the meso-level, a general decrease in distances and an increase in angles between attacking and defending players were observed between successful to unsuccessful penetrative passes. CONCLUSIONS: These findings highlight the importance of using positional data analysis to identify teams' tactical profiles and to potentiate coaches' interventions.


Assuntos
Desempenho Atlético , Futebol Americano , Futebol
10.
Cells ; 12(12)2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37371104

RESUMO

Escherichia coli is a versatile commensal species of the animal gut that can also be a pathogen able to cause intestinal and extraintestinal infections. The plasticity of its genome has led to the evolution of pathogenic strains, which represent a threat to global health. Additionally, E. coli strains are major drivers of antibiotic resistance, highlighting the urgent need for new treatment and prevention measures. The antigenic and structural heterogeneity of enterohaemorrhagic E. coli colonisation factors has limited their use for the development of effective and cross-protective vaccines. However, the emergence of new strains that express virulence factors deriving from different E. coli diarrhoeagenic pathotypes suggests that a vaccine targeting conserved proteins could be a more effective approach. In this study, we conducted proteomics analysis and functional protein characterisation to identify a group of proteins potentially involved in the adhesion of E. coli O157:H7 to the extracellular matrix and intestinal epithelial cells. Among them, OmpA has been identified as a highly conserved and immunogenic antigen, playing a significant role in the adhesion phenotype of E. coli O157:H7 and in bacterial aggregation. Furthermore, antibodies raised against recombinant OmpA effectively reduced the adhesion of E. coli O157:H7 to intestinal epithelial cells. The present work highlights the role of OmpA as a potent antigen for the development of a vaccine against intestinal pathogenic E. coli.


Assuntos
Escherichia coli O157 , Proteínas de Escherichia coli , Animais , Escherichia coli O157/genética , Proteínas de Transporte , Proteômica , Proteínas de Escherichia coli/genética , Colágeno
11.
Sci Rep ; 13(1): 6872, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37106029

RESUMO

Sjögren's Syndrome (SjS) is a chronic systemic immune-mediated inflammatory disease characterized by lymphocytic infiltration and consequent lesion of exocrine glands. SjS diagnosis and classification remains a challenge, especially at SjS onset, when patients may have milder phenotypes of the disease or uncommon presentations. New biomarkers are needed for the classification of SjS, thus, we aimed to evaluate the added-value of lymphocyte subpopulations in discriminating SjS and non-Sjögren Sicca patients. Lymphocyte subsets from 62 SjS and 63 Sicca patients were characterized by flow cytometry. The 2002 AECG and the 2016 ACR/EULAR SjS classification criteria were compared with clinical diagnosis. The added discriminative ability of joining lymphocytic populations to classification criteria was assessed by the area under the Receiver-Operating-Characteristic Curve (AUC). Considering clinical diagnosis as the gold-standard, we obtained an AUC = 0.952 (95% CI: 0.916-0.989) for AECG and an AUC = 0.921 (95% CI: 0.875-0.966) for ACR/EULAR criteria. Adding Tfh and Bm1 subsets to AECG criteria, performance increased, attaining an AUC = 0.985 (95% CI: 0.968-1.000) (p = 0.021). Th1/Breg-like CD24hiCD27+ and switched-memory B-cells maximized the AUC of ACR/EULAR criteria to 0.953 (95% CI: 0.916-0.990) (p = 0.043). Our exploratory study supports the potential use of lymphocyte subpopulations, such as unswitched memory B cells, to improve the performance of classification criteria, since their discriminative ability increases when specific subsets are added to the criteria.


Assuntos
Síndrome de Sjogren , Humanos , Síndrome de Sjogren/diagnóstico , Subpopulações de Linfócitos , Curva ROC , Diagnóstico Diferencial , Células B de Memória
12.
Insects ; 14(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37999060

RESUMO

Understanding how biodiversity varies from place to place is a fundamental goal of ecology and an important tool for halting biodiversity loss. Parasitic wasps (Hymenoptera) are a diverse and functionally important animal group, but spatial variation in their diversity is poorly understood. We survey a community of parasitic wasps (Ichneumonidae: Pimplinae) using Malaise traps up a mountain in the Brazilian Atlantic Rainforest, and relate the catch to biotic and abiotic habitat characteristics. We find high species richness compared with previous similar studies, with abundance, richness, and diversity peaking at low to intermediate elevation. There is a marked change in community composition with elevation. Habitat factors strongly correlated with elevation also strongly predict changes in the pimpline community, including temperature as well as the density of bamboo, lianas, epiphytes, small trees, and herbs. These results identify several possible surrogates of pimpline communities in tropical forests, which could be used as a tool in conservation. They also contribute to the growing evidence for a typical latitudinal gradient in ichneumonid species richness, and suggest that low to medium elevations in tropical regions will sometimes conserve the greatest number of species locally, but to conserve maximal biodiversity, a wider range of elevations should also be targeted.

13.
Mem Inst Oswaldo Cruz ; 107(3): 362-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22510832

RESUMO

We describe the abiotic factors affecting the distribution of black flies at a microhabitat scale, rather than at the regional scale usually present in the literature on the Neotropics. Black fly larvae were sampled from the Tocantins River and three tributaries, located in the Brazilian savanna (state of Tocantins, Brazil) during six bi-monthly sampling periods from October 2004-August 2005. At each sampling site, 15 random quadrats (30 x 30 cm) were sampled each period and for each quadrat were determined mean water velocity, predominant substrate type (rocks, riffle litter or riparian vegetation) and depth detrended correspondence analysis (DCA) was used to determine associations with current velocity, whereas correspondence analysis (CA) was used to estimate site specific current velocity associations. Canonical correspondence analysis (CCA) was used to identify general microhabitat associations. The CCA showed that most species had a trend towards riffle litter, except for Simulium nigrimanum associated with rocky substrate and Simulium cuasiexiguum associated with riparian vegetation. The DCA showed a well defined pattern of water velocity associations. The CA revealed that the species showed different speed associations from one site to another, suggesting different competitive pressures resulting in the occurrence of different realized niches.


Assuntos
Biodiversidade , Simuliidae/classificação , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional , Rios , Clima Tropical
14.
Foods ; 11(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35954025

RESUMO

Native potato starch has a semi-crystalline structure associated with a low glycemic index. Microwave vacuum drying (MWVD) produces crispy snacks under mild temperatures, reducing starch structural changes. However, blanching pretreatment gelatinizes starch, reducing crystallinity. A promising alternative is drying raw or blanched-then-cooled potatoes by MWVD. Cooling the blanched potato before MWVD aims to promote the partial return of the crystalline structure. Thus, this study evaluated how different pretreatments affect potato chips' starch structure and physical properties. Three samples were dried by MWVD: (i) raw (MWVD-RW), (ii) blanched (MWVD-BL), and (iii) blanched followed by cooling (4 °C for 48 h) (MWVD-BLC) potatoes. MWVD-RW samples presented a higher starch crystallinity (16.9%), which disappeared in MWVD-BL samples and partially returned in MWVD-BLC (8.7%). MWVD-BL and MWVD-BLC samples presented lower bulk (<0.338 g cm−3) density and higher porosity (>74%) and crispness. On the other hand, MWVD-BLC samples presented intermediate characteristics for color, true density, and porous distribution compared to others. All samples showed high porosity (>69%) and crispy texture. Therefore, based on the quality assessment, the MWVD-RW and MWVD-BLC produced healthy and crispy oil-free chips with a potentially lower glycemic index.

15.
Front Psychol ; 12: 694868, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354639

RESUMO

This study proposed a model to examine the role of self-efficacy, career goals, and athletic identity (AI) on the career planning of elite soccer players. Two hundred and eighty-one elite soccer players (males) participated in this study. Means, SD, and bivariate correlations were calculated for the variables under analysis. The hypothesized effect of self-efficacy, career goals, and AI on career planning was tested using structural equation modeling (SEM). Results supported the adequacy of the proposed model in explaining the career planning. Career planning is positively influenced by the level of self-efficacy of players through the definition of career goals and is negatively influenced by the level of AI. At the same time, the self-efficacy of players through the definition of career goals positively influenced AI. These findings reinforce the important role of self-efficacy and career goals for the development of AI and career planning and at the same time the opposite relationship between AI and career planning. Thus, it is suggested that a balance on AI, maintaining high levels of self-efficacy and career goals, is required to improve the process of career planning and retirement.

16.
Zookeys ; 1041: 137-165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36760416

RESUMO

The Neotropical Polysphinctadizardi species-group is revised. We describe seven new species from South America: P.bonita sp. nov., P.cosnipata sp. nov., P.inca sp. nov., P.macroepomia sp. nov., P.organensis sp. nov., P.pichincha sp. nov., and P.teresa sp. nov. In addition, we provide a diagnosis and an identification key to all species of the group.

17.
J Proteomics ; 232: 104025, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33160105

RESUMO

Among diarrheagenic E. coli (DEC), enterohaemorrhagic E. coli (EHEC) are the most virulent anthropozoonotic agents. The ability of bacterial cells to functionally interact with their surrounding essentially relies on the secretion of different protein effectors. To experimentally determine the repertoire of extracytoproteins in E. coli O157:H7, a subproteomic analysis was performed not only considering the extracellular milieu but the cell surface and outer membrane vesicles. Following a secretome-based approach, the proteins trafficking from the interior to the exterior of the cell were depicted considering cognate protein transport systems and subcellular localisation. Label-free quantitative analysis of the proteosurfaceome, proteovesiculome and exoproteome from E. coli O157:H7 grown in three different nutrient media revealed differential protein expression profiles and allowed defining the core and variant subproteomes. Network analysis further revealed the higher abundance of some protein clusters in chemically defined medium over rich complex medium, especially related to some outer membrane proteins, ABC transport and Type III secretion systems. This first comprehensive study of the EHEC secretome unravels the profound influence of environmental conditions on the extracytoplasmic proteome, provides new insight in the physiology of E. coli O157:H7 and identifies potentially important molecular targets for the development of preventive strategies against EHEC/STEC. SIGNIFICANCE: Escherichia coli O157:H7 is responsible for severe diarrhoea especially in young children. Despite years of investigations, the global view of the extracytoplasmic proteins expressed in this microorganism was eluded. To provide the first comprehensive view of the secretome landscape of E. coli O157:H7, the exoproteome, proteosurfaceome and proteovesiculome were profiled using growth conditions most likely to induce changes in bacterial protein secretion. The profound influence of growth conditions on the extracytoplasmic proteome was unravelled and allowed identifying the core and variant subproteomes. Besides new insight in the physiology of enterohaemorrhagic E. coli, these proteins potentially constitute important molecular targets for the development of preventive strategies.


Assuntos
Escherichia coli O157 , Proteínas de Escherichia coli , Proteoma
18.
Acta Ophthalmol ; 99(8): e1315-e1325, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33683020

RESUMO

PURPOSE: To assess and compare corneal sub-basal nerve plexus morphology with circulating lymphocyte subsets, immunologic status and disease activity in Sjögren syndrome (SjS) patients. METHODS: Fifty-five SjS patients, 63 Sicca patients (not fulfilling SjS criteria), 18 rheumatoid arthritis (RA) patients and 20 healthy controls (HC) were included. Systemic disease activity in SjS was assessed with the ESSDAI score. Lymphocyte subpopulations were studied with flow cytometry. Corneal confocal microscopy and ImageJ software were used to characterize corneal sub-basal nerve plexus in terms of nerve density (CNFD), length (CNFL) and tortuosity (CNFT). Conventional dry eye tests were also performed. RESULTS: CNFL and CNFD were lower in SjS, Sicca and RA groups, compared to HC (p < 0.001 for both SjS and Sicca); CNFL p = 0.005, CNFD p = 0.018 in RA). CNFT was higher in SjS, followed by Sicca, RA and HC. A negative correlation was found between ESSDAI score and CNFL (r=-0.735, p = 0.012). CNFL correlated negatively with IL21+ CD8+ T cells (r=-0.279, p = 0.039) and a positively with total memory (r = 0.299, p = 0.027), unswitched memory (r = 0.281, p = 0.038) and CD24Hi CD27+ (r = 0.278, p = 0.040) B cells. CNFD showed a tendency to significance in its negative correlation with ESSDAI (r=-0.592, p = 0.071) and in its positive correlation with switched memory B cells (r = 0.644, p = 0.068). CONCLUSIONS: This is the first study aiming to correlate ocular findings with lymphocyte subsets in SjS. The associations founded between CNFL and CNFD and disease activity, IL21+ follicular T cells and some B-cell subsets suggest that corneal nerve damage may parallel systemic disease activity and inflammatory cells' dynamics.


Assuntos
Córnea/inervação , Imunidade Celular , Subpopulações de Linfócitos/patologia , Fibras Nervosas/patologia , Síndrome de Sjogren/diagnóstico , Lágrimas/citologia , Contagem de Células , Córnea/imunologia , Córnea/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Fibras Nervosas/imunologia , Síndrome de Sjogren/imunologia
19.
Sci Rep ; 11(1): 4082, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603079

RESUMO

Sjögren's syndrome (SjS) is characterized by lymphocytic infiltration of exocrine glands, i.e. autoimmune epithelitis. Lymphocytes are central in SjS pathogenesis, with B-cell hyperactivity mediated by T-cells. B-cells are main targets of Epstein-Barr virus (EBV) infection, a frequently-suggested trigger for SjS. We aimed to evaluate how the EBV infection modulates B and T-cell subsets in SjS, including as controls Rheumatoid arthritis patients (RA) and healthy participants (HC). SjS patients presented decreased CXCR5+T-cells, although IL21-secreting Tfh and Tfc cells were increased. Tfc were positively correlated with ESSDAI scores, suggesting their relevant role in SjS pathogenesis. As previously described, SjS patients showed expanded circulating naïve B-cell compartments. SjS patients had a higher incidence of EBV-EA-D-IgG+ antibodies, characteristic of recent EBV-infection/reactivation. SjS patients with past infection or recent infection/reactivation showed increased CXCR3+Th1 and CXCR3+Tfh1 cells compared to those without active infection. SjS patients with a recent infection/reactivation profile presented increased transitional B-cells compared to patients with past infection and increased plasmablasts, compared to those without infection. Our results suggest EBV-infection contributes to B and T-cell differentiation towards the effector phenotypes typical of SjS. Local lymphocyte activation at ectopic germinal centres, mediated by Tfh and Tfc, can be EBV-driven, perpetuating autoimmune epithelitis, which leads to gland destruction in SjS.


Assuntos
Doenças Autoimunes/imunologia , Encefalite/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4 , Síndrome de Sjogren/imunologia , Doenças Autoimunes/sangue , Doenças Autoimunes/congênito , Doenças Autoimunes/virologia , Subpopulações de Linfócitos B , Estudos de Casos e Controles , Encefalite/sangue , Encefalite/virologia , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Feminino , Citometria de Fluxo , Humanos , Síndrome de Sjogren/sangue , Síndrome de Sjogren/etiologia , Síndrome de Sjogren/virologia , Subpopulações de Linfócitos T
20.
Zootaxa ; 4719(1): zootaxa.4719.1.1, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-32230647

RESUMO

Acrotaphus Townes, 1960 is a moderately large New World genus of spider attacking parasitoid wasps. Previously, it comprised 11 species. The present study aims to review the genus, and includes descriptions of 15 new species: A. amajari sp. n., A. amazonicus sp. n., A. bodoquenaensis sp. n., A. cuzconus sp. n., A. dolichopus sp. n., A. homeofranklini sp. n., A. jackiechani sp. n., A. kourou sp. n., A. micrus sp. n., A. monotaenius sp. n., A. nambilloensis sp. n., A. pseudoamazonicus sp. n., A. pseudomexicanus sp. n., A. venezuelanus sp. n. and A. zampieronae sp. n.. In addition, we present new characters for the study of the genus and describe the male genitalia for the first time. An illustrated key and maps to the species of the genus are provided. Acrotaphus franklini Gauld, 1991 and A. pseudoamazonicus sp. n. were recorded from the nests of Trypoxylon (Trypargilum) lactitarse Saussure, 1867 (Hymenoptera: Crabronidae).


Assuntos
Himenópteros , Vespas , Animais , Masculino
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